Twist-on wire connectors are well-known devices for making connections between two or more electrical wires. The connectors typically have a hollow shell or cap of insulating material. The shell is also sometimes referred to as a housing or body. The interior surface of the shell is threaded to enable the shell to grip the conductors tightly and retain the connector on the ends of the wires. The threads are often formed by a coiled metal spring inserted into the shell. The outside edges of the spring are embedded in the inner walls of the shell to hold the spring in the shell and prevent it from pulling out. The interior edges of the coil spring are engageable with the stripped ends of the wires.
Installation of a twist-on connector involves stripping the insulation from the ends of the wires and inserting the exposed conductors into the shell. Then the user twists the shell to seat the conductors firmly in the threads. It is not ordinarily necessary to pre-twist the wires as the twisting action of installation will sufficiently compress the wires together to make a sound electrical connection. The twisting action is most commonly performed using just the installer""s fingers, although many connectors are designed to be compatible with ordinary wrenches or specialized wrenches so extra torque can be applied if desired. However, it is possible to apply too much torque which causes failure of the shell such as by driving the wires through the closed end of the shell. Accordingly, most electrician""s prefer not to bother with pulling out a tool to apply a connector. They just use their fingers because that""s the quickest, most convenient way to get the job done. Furthermore, many connector designs employ extensions commonly known as wings which provide an enlarged gripping surface for the thumb and forefinger to enable application of sufficient torque. While applying connectors with the fingers is normally fully effective, prolonged, repeated installation in this manner can lead to discomfort and fatigue. When a job requires installation of numerous connectors, the hard, plastic surface of the shell can be a pain in the fingers. Also, the usual plastic shell surface can be slippery in instances where the user""s fingers are sweaty or soiled.
Dual durometer twist-on connectors having a shell with a rigid upper body and a flexible lower skirt are taught in U.S. Pat. No. 5,132,494. This connector does not place the flexible material on top of the rigid material to form a cushioned grip and all the twisting forces would have to be placed on the rigid body portion. U.S. Pat. No. 5,151,239 discloses a twist-on connector formed within an outer shell or housing having gripping ridges but these ridges do not provide a cushioned grip.
The present invention provides a twist-on wire connector with an enhanced feel for improved gripping ability and cushioning. The connector has a shell of conventional interior construction but with an exterior surface having a cushioned grip. In one embodiment the exterior surface is modified from the conventional construction to facilitate forming the cushioned grip thereon. In a second embodiment the cushioned grip is formed on a standard exterior surface. The cushioned grip has a higher coefficient of friction and a lower hardness than typical shell materials, thereby making the connector both easier to grip and more comfortable on the fingers. The improved grip reduces the need for the user to squeeze the connector as hard. This reduces fatigue when numerous connectors have to be applied. The exterior surface of the shell may have a grip mounting portion with clearly defined edges or boundaries. These edges provide a positive stop to keep the grip material from leaking during molding.